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There is an interesting article by Thom Hogan. Many of you may know all this, but for me there were elements I did not know. Here is a link: http://www.bythom.com/ . I knew that DOF is greater with lenses of identical focal length and aperture, but I did not know the numerical relationship. I also liked how he described the different uses of larger and smaller sensor lenses of similar aperture. I will in due course (5 years or so) switch to a sensor of less than APS-C (physical stamina is not the same as you get older). One of the concerns I have is that the zooms for m4/3 are relatively slow and so if/when I switch, I will probably go for a system of about 3 primes. As I have a good sense how often and when I use shallow DOF, understanding the relationship between the angle of view (expressed here indirectly, all other things being equal as a sensor size) and DOF is helpful. Perhaps it is of use to some of you when migrating from one sensor size to another.
That will be an excellent time to switch as the entire mirrorless and compact camera sector of the market is in a Renaissance period. By that time, the key players should have settled in, and the flash in the pan players should have drifted away. IMO, the key thing missing from *most* of the current products in this space is the lack of a proper optical viewfinder - i.e. one that changes view as you zoom. Fuji seems to be trying to address this deficiency, and the others can't be too far behind.

As for lens choices, I am greatly encouraged by the lenses that have been added to the m43 stable over the last year. There is now a full set of quality fast primes available. Can faster zooms be far behind? There is currently an implicit lens equation that says: size, speed, and price. Pick 2. Technology romps along, though - so who knows what the future will bring...
Robert, I agree about m4/3 - it has a decent collection of primes (I am less interested in zooms at this point), lenses and cameras are small & light enough (otherwise, why switch?). LCDs and electronic viewfinders are steadily improving. Like you, I was a firm believer in optical viewfinder and absence of optical viewfinder was a deal breaker for me. However, the LCDs are now a lot brighter and with decent resolution (if not color accuracy - but I care less about that in camera LCD or viewfinder). Electronic viewfinders are improving at an unbelievable pace and already I would prefer a good EVF to a small, crappy OVF that seems to be the usual case in non-DSLRs (I know of some exceptions). Optical viewfinder takes up a lot of rea estate, is expensive to make and I expect further improvements in EVFs over 5 year span. So I am dropping my categorical objections to EVFs. I will be paying attention to sensor quality and lens quality/selection when I take my pick. Currently my pick would be m4/3 because of the lenses, although Olympus sensor in particular seems to be lagging behind and I would like to have built in viewfinder. Sonny is a nonstarter. The body is small but the lenses are not much smaller than my current clutch. I do not want a heavy, unballanced system with few lenses to choose from. Nikon is not for me - not the controls i want and lenses are too few, too big and too expensive while the sensor is small. Other systems currently have too few lenses to consider.
Agree with everything you say - but I am not so fast to dismiss the idea of having a quality OVF in a compact package - particularly if you can afford to play wait and see. Check out the viewfinder in the Fuji X10 for a good example of a first cut at a zooming OVF that is bright and a good size. Imagine where that will go in the next 5 years if Fuji (and others) continue to innovate.

http://www.fujifilm.ca/products/digital_...ge_03.html
I am far from dismissing OVF. I am more or less resigned to the inevitable (as I read the tea leafs) and I expect that there will not be much choice when it comes to OVF in a few years. I generally prefer OVF, but still I think that EVF has improved so much that it is now a credible alternative. I generally like the direction Fuji has been going for good many years with their sensors, with the importance they place on dynamic range and color over sheer resolution, the idea behind X100 (but not quite the current iteration of this camera). Any system I pick will have to have all the lenses I ever EXPECT to need (as opposed to buy) at the time I purchase the camera. I am thinking ultrawide ( certainly no longer than 24 mm equiv), wide/normal (between 35mm and 50 mm), moderate tele (100 or 150), long tele (?) (about 300 mm). The idea is that the prime focal lengths will be double/half the focal lengths of the nearest neighbours. One lens (preferably moderate tele) would also be a 1:1 macro. I expect to end up with 3 lenses initially and eventually add one lens. I hope that depending on the sensor size, the primes were f/2 or wider. If the camera had APS-C sensor, I would consider slower zooms.
There are some pretty darn nice EVFs out there - the one that Olympus packaged with the EP-2 for example (not the new one) or the internal one on the Panansonic GH-1 / GH-2. I.m not a fan of external EVFs though - just another fiddly bit. Also, all EVFs that I have tried so far start to degrade massively in low light. But like all other technologies, I am sure these will continue to improve by leaps and bounds.
Bit late to the party but thanks for the article and it's a very good read. Most people know about the sensor crop factor, and I was aware that smaller sensors will give you greater equivalent depth of field but it's eye opening when you compare figures in that manner.

Case in point:

Quote:But the opposite is true, too. Let's turn things around and say that we want lots of depth of field: [NOTE: I think the author meant shallower depth of field here]

Coolpix shooter is at 6mm f/2.8
Nikon 1 shooter is at 10mm f/4
m4/3 shooter is at 14mm f/5.6
DX shooter is at 18mm f/8
FX shooter is at 28mm f/11
It's quite scary that the compact at its shallowest depth field at f/2.8 is equivalent of a full frame at f/11 or APS-C at f/8. Makes the job much harder if you want to isolate your subject or take some nice portraits...
shuttertalk Wrote:It's quite scary that the compact at its shallowest depth field at f/2.8 is equivalent of a full frame at f/11 or APS-C at f/8. Makes the job much harder if you want to isolate your subject or take some nice portraits...
Yes indeed - that "everything in focus" side effect of sensor sizing gives Point and Shoots their distinctive "look"... Big Grin
shuttertalk Wrote:Case in point:

Quote:But the opposite is true, too. Let's turn things around and say that we want lots of depth of field: [NOTE: I think the author meant shallower depth of field here]

Coolpix shooter is at 6mm f/2.8
Nikon 1 shooter is at 10mm f/4
m4/3 shooter is at 14mm f/5.6
DX shooter is at 18mm f/8
FX shooter is at 28mm f/11
It's quite scary that the compact at its shallowest depth field at f/2.8 is equivalent of a full frame at f/11 or APS-C at f/8. Makes the job much harder if you want to isolate your subject or take some nice portraits...
No, the author did not mean shallower depth of field. Lots of depth of field is often a good thing. Yes, really! Landscapes, macro, large group portraits, architecture, ...

The purpose for small sensors is to get deep depth of field at bright apertures. The purpose for large sensors is to get shallow depth of field without insanely expensive lenses.
Nice to see a new poster who isn't a spammer. Hi blue.
Blue, welcome to the forum. I'm completely in agreement with Toad on this: it's great to see you. I find that more of my photos are hurt by having not enough in focus than by having too much, but then I've never been into portraits.

General thoughts, hopefully somewhat relevant:

Some of the newer advanced compacts, like the Olympus XZ-1, can have as much control over depth of field as a 1.5x SLR with its kit lens at 55mm and f/5.6.

All sensor/film sizes start to have diffraction affect their sharpness at the about the same apparent depth of field.

Electronic viewfinders can be tricked into displaying a monochrome image while the raw files always remain in full colour, which can be handy. The EVF on my old Sony F828 would automatically switch to monochrome in low light; I wish my GH1 would do this as well. (Our low-light vision is monochrome anyway.)

If I didn't have my current collection, I might be tempted to get an Olympus E-P3 (for its image stabilization) or Panasonic G3 (for the EVF and flip-out screen) to use with the 12/2.0, 20/1.7, and 45/1.8 lenses. (Or 14/2.5, 25/1.4, 45/2.8…)
It seems that to really get a tool that can do everything, you need lots of money. And even if you want to play at the extremes you need lots of dough - large sensors $$$ or high-quality small sensor/lens combos $$$.

But even if you only want to do two different kinds of shots, if those types of shots are really different, the most efficient way to get everything you need might be to use more than one format. For example,

Wanting to do both:
a) shallow depth of field, slow shutter speed, wide angle (romantic waterfall portraits) ---> large format
b) handheld interior architecture ---> small format

Wanting to do both:
a) low light compressed landscape with birds frozen in flight; telephoto, high shutter speeds, large DOF ---> small format
b) casual interior medium-length portraits with OOF background; shallow DOF, normal angle of view ---> large format

I'm just glad to be an amateur and not have to worry about being able to do everything. And excited that the small formats are getting higher quality, and the large formats are getting cheaper! Lots of fun ahead.
@Matthew, I think that all cameras have their limitations (capabilities, options/additions, price, weight etc.) Obviously in the best of worlds one would have a camera lens combination ideally suited for each job. It is a sensible approach for many circumstances if you have the knowledge, money, space and inclination to gather and use all the "right" equipment. An alternative approach, which I see is defensible too is to examine your photo needs and interests and fine one camera system with a mix of properties which meet your needs well enough most of the time. That is my approach. The key is to understand both your needs and wants well and to understand the strengths and limitations well enough in advance to make sure that there is a reasonable match. I do not expect a perfect match and I certainly do not blame the manufacturer for targeting somebody with different mix of needs and wants than my own. There are 3 reasons why I do not adopt your strategy of many camera bodies:
1) I do not wish to process film and to get the same range in digital cameras would be expensive or impossible.
2) I do not wish to learn how to operate multiple cameras. I rely on instinctual familiarity with one camera and i feel that I would loose that if i had several different cameras. In my age, such instinctual familiarity is slow to develop and easy to confuse.
3) Unlike you, I often travel for longer stretches of time to areas I do not know, I will probably never have a chance to revisit and I do not know ahead of time what I will encounter. I want to have a simple integrated system that will help me deal with most eventualities, whatever they turn out to be.
4) My photographic interests are extremely wide. My fascination with photography comes from camera's ability to help me to notice and to visually explore things around me that I would normally ignore. The things that catch my attention call for a fairly wide range of lenses to capture.

I theory, when I buy a smaller camera system in the future, I will still have the use of my DSLR-based system, so I will have the option to use either. In practice, I expect that if a lot of walking will be involved, I will go with lighter system.

Having 2 parallel systems as your friends have is a good idea (supported by good rationale behind it) and one obviously within reach for those that can afford a D3s - based system (my dream camera), but it is an expensive solution and I am not prepared to do that at this time.
Good points everyone... I think that's the perceived appeal of a interchangeable lens system - with one body you can swap out your different lenses (like using different tools) to get a desired effect or usage. What most don't realise is, and the author is highlighting, is that switching sensor sizes affects your end result more than just light sensitivity (and image quality).

I think for me, I like the concept of a smaller system as an alternative to (and not a replacement) to my main system. This decision will be based mainly around portability and the choice as to which system to take out the door will be balanced against those aforementioned tradeoffs.

Welcome to Shuttertalk by the way, blue! Big Grin